Introduction to the Basic Encoder
Page 1-10
Reference Guide: Voyager E5784 and E5788 HD DSNG Encoder
ST.RE.E10137.3
These signals may be processed using the encoding modes in the following
section.
MPEG Encoding Modes
The two stereo pairs may be configured in various encoding modes:
•
Single mono: either the left or the right channel is encoded.
•
Dual mono: the left and right signals are encoded and carried in the
transport stream as a single Packetised Elementary Stream (PES) data
stream. The way that the left and right signals are output from the
Receiver is dependent on how the routing is set up on the Receiver.
Both the left and the right may be output, or the left only, or the right
only. This is typically used for multilingual services. Available in
MPEG-1 (layer 2) and Linear PCM.
•
Stereo: A stereo pair is coded as two mono signals - the two signals
are output as stereo at the receiving end.
•
Joint stereo: A stereo pair is coded taking advantage of the stereo
nature of the channels - the two signals are output as stereo at the
receiving end. Available in MPEG-1 (layer 2) only.
•
Audio Description Service
Dolby Digital (AC-3) Encoding Modes
•
1/0: centre
•
2/0: left and right
Test Tones
The equipment can be configured to generate a test tone for alignment
purposes. Refer to Annex B, Technical Specification for level and
frequency.
Audio Variable Bit-rate
MPEG-1 audio output bit-rate (see Annex B, Technical Specification) is
selectable in the range 32 kbit/s -384 kbit/s (dependent on configuration).
Dolby Digital (AC-3)
Dolby Digital (AC-3) audio encoding incorporates digital normalisation,
preprocessing (filtering), dynamic range compression and the addition of
bit-stream information.
Dolby Pro Logic audio can be carried as stereo audio through the Encoder
as long as a suitably high bit-rate is selected (see Annex B, Technical
Specification).
1.3.3
Vertical Blanking Interval (VBI) Line Processing
Modes (SD)
Introduction
The Encoder has three modes for processing VBI lines.
NOTE…
A maximum of eight VBI lines per field may be extracted. This limit does not apply to Teletext.
